摘要:
A bias voltage stabilizing method for an electricity-optical modulator based on an off-level sampling is disclosed. The method includes the steps of a first step for detecting an electric signal by feed-back an output optical signal of a MZ optical modulator, performing a sample and hold for an OFF level and converting the signal into a digital data, a second step for receiving the sample and hold data with respect to the OFF level, controlling a bias value by performing an up and down count so that a minimum operation level is maintained at near a zero level of an output optical signal based on a binary data and a current data value, and adjusting a bias value, and a third step for outputting a bias control voltage of an optical modulator by converting the bias value controlled by the up and down count into an analog signal, for thereby controlling an adaptive bias voltage irrespective of a traffic characteristic of a signal by selectively extracting an OFF level of an output light, measuring the thusly extracted level and minimizing the value for thereby controlling a bias voltage.
摘要:
A spatial switch of a simple structure using a "M.times.N" optical beam steering device which operates with M "1.times.N" spatial switches using a phased optical waveguide array. The spatial switch using an optical beam steering device in accordance with the present invention is characterized in that the optical beam steering device includes an optical waveguide phase modulator array, the optical beam steering device is used as a "1.times.N" spatial switch device, and M units of the "1.times.N" spatial switch device are aligned in parallel so that a "M.times.N" spatial switching operation is performed on a plane where a far field diffraction pattern of the "1.times.N" spatial switch device is formed. The spatial switch utilizes the characteristics that if the propagation directions of the lights output from "1.times.N" switches coincide with each other, the far field diffraction patterns formed by the switches converge into the same point.
摘要:
An electro-optic polymer waveguide device capable of decreasing a driving voltage and an optical loss is disclosed. A vertical tapered waveguide is formed between passive waveguides of input and output portions in a waveguide and an electro-optic modulating region, and an amplitude of a waveguide mode of the input and output portion waveguide is equal to that of a optical fiber, thereby minimizing a connection loss with the optical fiber.